Insert for concrete construction.



VV. Nl. PRATT.

INSERT FOR CONCRETE CONSTRUCTION.

APPLICATION HLED FEB. 10, 191i.

LQSLML@ 'Patented 00h15, 1918.

2 SHEETS-SHEET 2.

VVE-.LTER M.. PRATT, 0F DETROIT, MICHIGAN.

INSERT FOB, CONCRETE CONSTRUCTION.

Specification of Letters Patent. Pattgmttdl (met, 15, 1918.,

Application filed February 10, I917. Serial No. 147,835.

VTo all whomc't may concern.'

Be it known that I, WALTER M; PRATT, a citizen ofthe United States, residin at De troit, in the county of Wayne and tate of Michigan, have invented new and useful Insert for Concrete Construction, of which the following is a specification.

The inventionrelates to inserts for cencrete construction, and its object is to provide an insert comprising an elongated channel member adapted to be embedded and anl concrete floor; Fig. 2 is a bottom View of the same; Fig. 3 is a section on 3 3 of Fig. l; Iligs. 4, 5, and 6 are corresponding views of' a modified form.

In these views, the reference character 1 designates a concrete floor, having two trans-- versely arranged sets of reinforcing bars 2 and 3 extending horizontally in its lower portion. Embedded in said floor is a channel member e, formed preferably of sheetmetal, the sides of said member being in clined downwardly7 toward each other, so as to form a slot 5 between their lower extremities, and said extremities being formed with out-turned flanges 6 flush with the under surface of the'loor. At intervals the inclined walls of the member 4 are formed with pairs of opposite slots 7, adjacent the top of said member. In keach pair of these slots there are engaged the inturned lower ends 8 of an arch-shaped anchorage member 9, which may be formed of bar iron. The members 9 are embedded in the central portion of the floor and are suliciently numerous to resist the maximum Vdownward pull to which the channel member may be subjected.

il. slidably adjustable rider is engaged with the member a, which rider comprises a flared head 10 within the channel and resting upon the inclined sides thereof, a body 11, preferably of cylindrical form, projecting. some distance below'the floor, and shoulders l2, prajecting laterally beneath the respective flanges G and having top surfaces parallel and adjacent to said flanges. A. central threaded opening i3 extends up into the body of the rider from the bottom thereof, and an inverted bolt 14- has its shank engaged insaid opening. The headed lower end of the bolt may be engaged with a shaft hanger, pipehanger, (not shown)v or any other member which is to be supported from the ceiling.

At any desired point in the channel member, the slot 5 1s widened to form an entrance slot l5 by stamping opposite `tongues 'from the lower portion of the in;

clined side walls of said .member and from the flanges G. -The Vupper portions 16 of these tongues are bent into vertical parallelism and their lower portions 17 are in the' plane of the flanges and project somewhat beyond the same. The dimensions of said .entrance slotare a trifle greater than those of the head 10 at the widest part of the lat# ter, so that when the channel is in place `in the floor, the rider or riders may be engaged with or disengaged from the channel by use Aof said entrance slot. vHoles 18 may be provided inthe flanges 6 at suitable intervals, and nails or lother fastening means (not shown) ymay be driven through these holes and into the forms to hold the channel members and anchorage members securely in place during pouring. In order to prevent the concrete from' flowing into the channels as it is being poured. sheet-metal caps 19 are frictionally engaged with the extremities of the channel member at. l

In that form of the invention shown in Figs. et, 5, and 6, there is used a cha nel member and anchorage members sub tantially as above-described, and for these )arts the vreference characters are the same as: in the rst three figures. In this modification however the rider takes the form of a metal block 2O insertible as a whole into engagement with the channel, the lower port-ions of the sides being beveled asin the lirst-described rider to rest upon the inclined walls of the channel, but the upper portions of said sides being recessed as indicated at 2l as a clearance for the inturned ends of the anchorage members 9, while the top portion of the block projects between said ends. A screw-threaded opening 2Q extends centrally and vertically entirely through this rider, and is engaged bythe shank of a bolt 23.

Numerous advantages which will now be explained are derived from the above-described construction. Concrete floors are commonly reinforced by one or more series s floor bottom to afford adequate fire-proofing.

Thus in the drawings, two transversely `arranged 4series 24 and 25 are shown, formingthe well-known two Way system. For practically all reinforced concrete work, the minimum thickness of material below the reinforcement is three-fourths of an inch'. To'exceed this is highly undesirable since any thickness below the reinforcements in excess of the fireproofing requirements is entirely wasted, and uselessly increases.the weight of the iioor. Slotted channel inserts have hitherto been employed, shaped to slidably engage the heads of standard bolts, but in order to accommodate the bolt-heads, it has been requisite to give the channel inembers a height greater than the thickness of material required for fire-proofing, and conA sequently space the bars extending transversely above-said channel members an 1111-.

desirable distance above the floor bottom. In' the present invention, the usual fireprooing area below the barsA is ample to embed the channel members, since the portions of the riders engaged within the channels are given horizontal dimensions such as to secure adequate strength, with little height. Furthermore,said riders do not concentrate the downward Apull which they transmit, as vertical stresses in the concrete but because of the abutting inclinedl `faces produce a horizontal component ofsaid pull.

'The anchorage required is thus reduced as compared with an insert in which the -downf ward pull has no horizontal component.

The corresponding inclined faces of the channel walls and the rider further has the effect of causing the rider to become wedged more firmly in place by each increase in the load which it transmits to the floor. In the form of the invention shown in the first three figures the-shoulders 12 through their proximity to the flanges 6 serve to prevent lateral rocking of the rider when under load.

This r form of rider is, especially suitable where it is permissible to engage the bolt with the rider below the floor, while the form shown in Figs. 4, 5, and 6 may be used where it is dired to have the rider contained completely within the channel. t is tobe noted that the anchorage members are engaged with the channel members so as to be I restrained against longitudinal motion, thus eliminating necessity for adjustment of said anchorage members as the inserts are being arranged on the forms. y

iVhat I claim is:

l. The combination with an insert comprising a channel member having its walls inwardly inclined and a riderv having a. portion Iwithin the channel of said member Asupported upon said walls and having integral lateral projections exterior -to and below the channel-member, of means associated with the channel member at each side thereof coacting with said projections to restrain the rider from wabbling.

.2.- An insert, comprising 'a channel member having its Walls inwardly inclined and having out-turned flanges at the bottoms of said walls, and a rider having a portion within the channel of said member supportved upon said inclined walls and having integral portions extending adjacent to said flanges beneath the same.

3. The combination with an insert comprising a channel member and a rider adjustably retainedA in the channel of said member and having integral lateral projections below said member, of means'associated with the channel member at each side thereof vfor restraining the rider from wabbling. 'r

4. An insert, comprising a-channel member having flanges projecting laterally from its side walls and ariderhaving a portion" adjustably retained in the channel of said `member a'nd having integral portions pro- WALTER M. PRATT. 

